API Workflow

API Workflow node for invoking a published UiPath Studio Web API workflow and using its output, with its configuration fields and output variables.

Invokes a UiPath Studio Web API workflow and returns its output.

When to use API Workflow vs HTTP Request

Use the API Workflow node when the logic you need to call is built in Studio Web and published as an API workflow — for example, structured data processing or multi-step integrations authored by your team. Use the HTTP Request node when you are calling any external Representational State Transfer (REST) endpoint outside the UiPath Platform.

Configuration

Field	Required	Description
API workflow	Yes	The Studio Web API workflow to invoke. Select from the list of published API workflows in your organization.
Input	No	Key-value pairs mapped to the API workflow's input parameters. Supports variable references.
Timeout	No	Maximum time to wait for the workflow to complete.

Output variables

Variable	Description
output	The response returned by the API workflow, according to its output schema.
error	Error details when the call fails. Use it with error handling to branch on failures.

Examples

Reference the API workflow's output downstream with an expression:

$vars.apiWorkflow1.output

To use a single field from the output, append the field name defined by the API workflow's output schema — for example, $vars.apiWorkflow1.output.<field>.

Common issues

Issue	Resolution
API workflow not listed in the dropdown	Ensure the workflow is published in Studio Web and you have permission to invoke it.
Timeout error	Increase the Timeout value or optimize the Studio Web workflow for faster execution.
Input type mismatch	Check that the variable types you are passing match the API workflow's declared input parameter types.